Parallel edge guides for sheet offset

Abstract

A device for offsetting sheets as they are conveyed in a paper path toward a stacker includes a narrow channel mounted to a set of linked arms which when moved in a process direction (upstream-downstream) articulate in a cross process direction (inboard-outboard) to register the sheets at various locations for stacking or finish processing. The linked arms keep the channel parallel to the paper path at all times regardless of inboard-outboard offset.

What is claimed is: 
     
       1. An arrangement for offsetting sheets en route to a finishing station of a printer, comprising:
 a fixed rail; 
 a movable rail, said movable rail having a channel therein through which sheets are conveyed; 
 sets of linked arms connecting said fixed rail to said movable rail; and 
 actuators configured to provide movement to said movable rail and simultaneously provide movement to said sets of linked arms to thereby move said movable rail away from said fixed rail in a cross process direction. 
 
     
     
       2. The arrangement of  claim 1 , wherein said sets of linked arms are always parallel to each other. 
     
     
       3. The arrangement of  claim 2 , wherein said actuators include stepper motors and link pins. 
     
     
       4. The arrangement of  claim 2 , wherein said actuators include solenoids. 
     
     
       5. The arrangement of  claim 2 , wherein said sets of linked arms are positioned on a top portion of said movable rail and said fixed rail. 
     
     
       6. The arrangement of  claim 5 , wherein each of said sets of linked arms includes a first end thereof connected to an end portion of said movable rail and an end portion of said fixed rail. 
     
     
       7. The arrangement of  claim 6 , wherein each of said sets of linked arms includes a second end thereof connected to a portion of said movable rail and a portion of said fixed rail removed from an end portion thereof. 
     
     
       8. The arrangement of  claim 1 , wherein movement of said sets of linked arms in a process direction articulate said channel in said cross process direction to register sheets for stacking. 
     
     
       9. The arrangement of  claim 1 , wherein said sets of linked arms keep said channel parallel to a paper path at all times regardless of inboard-outboard offset. 
     
     
       10. An edge registration system that offsets sheets being conveyed within a paper path, comprising:
 a movable sheet edge registration guide, said movable sheet edge registration guide including a slit therein configured for movement of sheets therethrough as they are conveyed within said paper path; 
 a stationary guide positioned parallel to said sheet edge registration guide; and 
 a four bar linkage configured to variably position said movable sheet edge registration guide transversely while simultaneously maintaining parallelism of said movable sheet edge registration guide to said stationary guide. 
 
     
     
       11. The edge registration system of  claim 10 , wherein motion of said movable sheet edge registration guide is accomplished with an actuator. 
     
     
       12. The edge registration system of  claim 11 , wherein said motion of said sheet edge registration guide is created by rotation of a link of said four bar linkage by said actuator. 
     
     
       13. The edge registration system of  claim 11  wherein said motion of said sheet edge registration guide is created by a linear force acting normal to said sheet edge registration guide. 
     
     
       14. The edge registration system of  claim 13 , wherein said linear force acting normal to said sheet registration guide is provided by a cam. 
     
     
       15. The edge registration system of  claim 11 , wherein said actuator is a stepper motor. 
     
     
       16. A system for offsetting sheets as they are conveyed within a paper path toward a stacker, comprising:
 a movable bar including a channel therein adapted for the passage of sheets conveyed within said paper path; 
 a stationary bar positioned parallel to said movable bar; 
 and 
 a four bar linkage connected to said movable bar and said stationary bar such that when said four bar linkage is moved within a process direction said movable bar is articulated in a cross process direction to register sheets in various locations for stacking purposes. 
 
     
     
       17. The system of  claim 16 , wherein said four bar linkage keeps said channel within said movable bar parallel to said paper path at all times regardless of inboard-outboard offset. 
     
     
       18. The system of  claim 17 , wherein said movable bar is actuated by a solenoid. 
     
     
       19. The system of  claim 16 , wherein said movable bar is actuated by a stepper motor mounted on a link pin.